Commit Graph

477 Commits

Author SHA1 Message Date
Dominik Bozek b86b8eb6fe usb: cdc_acm: prevent race at write to acm while system resumes
ACM driver may accept data to transmit while system is not fully
resumed. In this case ACM driver buffers data and prepare URBs
on usb anchor list.
There is a little chance that two tasks put a char and initiate
acm_tty_flush_chars(). In such a case, driver will put one URB
twice on usb anchor list.
This patch also reset length of data before resue of a buffer.
This not only prevent sending rubbish, but also lower risc of race.

Without this patch we hit following kernel panic in one of our
stabilty/stress tests.

[   46.884442] *list_add double add*: new=ffff9b2ab7289330, prev=ffff9b2ab7289330, next=ffff9b2ab81e28e0.
[   46.884476] Modules linked in: hci_uart btbcm bluetooth rfkill_gpio igb_avb(O) cfg80211 snd_soc_sst_bxt_tdf8532 snd_soc_skl snd_soc_skl_ipc snd_soc_sst_ipc snd_soc_sst_dsp snd_soc_sst_acpi snd_soc_sst_match snd_hda_ext_core snd_hda_core trusty_timer trusty_wall trusty_log trusty_virtio trusty_ipc trusty_mem trusty_irq trusty virtio_ring virtio intel_ipu4_mmu_bxtB0 lib2600_mod_bxtB0 intel_ipu4_isys_mod_bxtB0 lib2600psys_mod_bxtB0 intel_ipu4_psys_mod_bxtB0 intel_ipu4_mod_bxtB0 intel_ipu4_wrapper_bxtB0 intel_ipu4_acpi videobuf2_dma_contig as3638 dw9714 lm3643 crlmodule smiapp smiapp_pll
[   46.884480] CPU: 1 PID: 33 Comm: kworker/u8:1 Tainted: G     U  W  O    4.9.56-quilt-2e5dc0ac-g618ed69ced6e-dirty #4
[   46.884489] Workqueue: events_unbound flush_to_ldisc
[   46.884494]  ffffb98ac012bb08 ffffffffad3e82e5 ffffb98ac012bb58 0000000000000000
[   46.884497]  ffffb98ac012bb48 ffffffffad0a23d1 00000024ad6374dd ffff9b2ab7289330
[   46.884500]  ffff9b2ab81e28e0 ffff9b2ab7289330 0000000000000002 0000000000000000
[   46.884501] Call Trace:
[   46.884507]  [<ffffffffad3e82e5>] dump_stack+0x67/0x92
[   46.884511]  [<ffffffffad0a23d1>] __warn+0xd1/0xf0
[   46.884513]  [<ffffffffad0a244f>] warn_slowpath_fmt+0x5f/0x80
[   46.884516]  [<ffffffffad407443>] __list_add+0xb3/0xc0
[   46.884521]  [<ffffffffad71133c>] *usb_anchor_urb*+0x4c/0xa0
[   46.884524]  [<ffffffffad782c6f>] *acm_tty_flush_chars*+0x8f/0xb0
[   46.884527]  [<ffffffffad782cd1>] *acm_tty_put_char*+0x41/0x100
[   46.884530]  [<ffffffffad4ced34>] tty_put_char+0x24/0x40
[   46.884533]  [<ffffffffad4d3bf5>] do_output_char+0xa5/0x200
[   46.884535]  [<ffffffffad4d3e98>] __process_echoes+0x148/0x290
[   46.884538]  [<ffffffffad4d654c>] n_tty_receive_buf_common+0x57c/0xb00
[   46.884541]  [<ffffffffad4d6ae4>] n_tty_receive_buf2+0x14/0x20
[   46.884543]  [<ffffffffad4d9662>] tty_ldisc_receive_buf+0x22/0x50
[   46.884545]  [<ffffffffad4d9c05>] flush_to_ldisc+0xc5/0xe0
[   46.884549]  [<ffffffffad0bcfe8>] process_one_work+0x148/0x440
[   46.884551]  [<ffffffffad0bdc19>] worker_thread+0x69/0x4a0
[   46.884554]  [<ffffffffad0bdbb0>] ? max_active_store+0x80/0x80
[   46.884556]  [<ffffffffad0c2e10>] kthread+0x110/0x130
[   46.884559]  [<ffffffffad0c2d00>] ? kthread_park+0x60/0x60
[   46.884563]  [<ffffffffadad9917>] ret_from_fork+0x27/0x40
[   46.884566] ---[ end trace 3bd599058b8a9eb3 ]---

Signed-off-by: Dominik Bozek <dominikx.bozek@intel.com>
Signed-off-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
Acked-by: Oliver Neukum <oneukum@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-16 07:52:55 +01:00
Linus Torvalds a9a08845e9 vfs: do bulk POLL* -> EPOLL* replacement
This is the mindless scripted replacement of kernel use of POLL*
variables as described by Al, done by this script:

    for V in IN OUT PRI ERR RDNORM RDBAND WRNORM WRBAND HUP RDHUP NVAL MSG; do
        L=`git grep -l -w POLL$V | grep -v '^t' | grep -v /um/ | grep -v '^sa' | grep -v '/poll.h$'|grep -v '^D'`
        for f in $L; do sed -i "-es/^\([^\"]*\)\(\<POLL$V\>\)/\\1E\\2/" $f; done
    done

with de-mangling cleanups yet to come.

NOTE! On almost all architectures, the EPOLL* constants have the same
values as the POLL* constants do.  But they keyword here is "almost".
For various bad reasons they aren't the same, and epoll() doesn't
actually work quite correctly in some cases due to this on Sparc et al.

The next patch from Al will sort out the final differences, and we
should be all done.

Scripted-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-02-11 14:34:03 -08:00
Linus Torvalds e4ee8b85b7 USB/PHY updates for 4.16-rc1
Here is the big USB and PHY driver update for 4.16-rc1.
 
 Along with the normally expected XHCI, MUSB, and Gadget driver patches,
 there are some PHY driver fixes, license cleanups, sysfs attribute
 cleanups, usbip changes, and a raft of other smaller fixes and
 additions.
 
 Full details are in the shortlog.
 
 All of these have been in the linux-next tree for a long time with no
 reported issues.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'usb-4.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb

Pull USB/PHY updates from Greg KH:
 "Here is the big USB and PHY driver update for 4.16-rc1.

  Along with the normally expected XHCI, MUSB, and Gadget driver
  patches, there are some PHY driver fixes, license cleanups, sysfs
  attribute cleanups, usbip changes, and a raft of other smaller fixes
  and additions.

  Full details are in the shortlog.

  All of these have been in the linux-next tree for a long time with no
  reported issues"

* tag 'usb-4.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (137 commits)
  USB: serial: pl2303: new device id for Chilitag
  USB: misc: fix up some remaining DEVICE_ATTR() usages
  USB: musb: fix up one odd DEVICE_ATTR() usage
  USB: atm: fix up some remaining DEVICE_ATTR() usage
  USB: move many drivers to use DEVICE_ATTR_WO
  USB: move many drivers to use DEVICE_ATTR_RO
  USB: move many drivers to use DEVICE_ATTR_RW
  USB: misc: chaoskey: Use true and false for boolean values
  USB: storage: remove old wording about how to submit a change
  USB: storage: remove invalid URL from drivers
  usb: ehci-omap: don't complain on -EPROBE_DEFER when no PHY found
  usbip: list: don't list devices attached to vhci_hcd
  usbip: prevent bind loops on devices attached to vhci_hcd
  USB: serial: remove redundant initializations of 'mos_parport'
  usb/gadget: Fix "high bandwidth" check in usb_gadget_ep_match_desc()
  usb: gadget: compress return logic into one line
  usbip: vhci_hcd: update 'status' file header and format
  USB: serial: simple: add Motorola Tetra driver
  CDC-ACM: apply quirk for card reader
  usb: option: Add support for FS040U modem
  ...
2018-02-01 09:40:49 -08:00
Greg Kroah-Hartman 7f26ee4b56 USB: move many drivers to use DEVICE_ATTR_RO
Instead of "open coding" a DEVICE_ATTR() define, use the
DEVICE_ATTR_RO() macro instead, which does everything properly instead.

This does require a few static functions to be renamed to work properly,
but thanks to a script from Joe Perches, this was easily done.

Reported-by: Joe Perches <joe@perches.com>
Cc: Matthieu CASTET <castet.matthieu@free.fr>
Cc: Stanislaw Gruszka <stf_xl@wp.pl>
Cc: Oliver Neukum <oneukum@suse.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Acked-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Acked-by: Pete Zaitcev <zaitcev@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-01-24 08:49:52 +01:00
Oliver Neukum df1cc78a52 CDC-ACM: apply quirk for card reader
This devices drops random bytes from messages if you talk to it
too fast.

Signed-off-by: Oliver Neukum <oneukum@suse.com>
CC: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-01-22 15:34:37 +01:00
Hans de Goede f0386c083c USB: cdc-acm: Do not log urb submission errors on disconnect
When disconnected sometimes the cdc-acm driver logs errors like these:

[20278.039417] cdc_acm 2-2:2.1: urb 9 failed submission with -19
[20278.042924] cdc_acm 2-2:2.1: urb 10 failed submission with -19
[20278.046449] cdc_acm 2-2:2.1: urb 11 failed submission with -19
[20278.049920] cdc_acm 2-2:2.1: urb 12 failed submission with -19
[20278.053442] cdc_acm 2-2:2.1: urb 13 failed submission with -19
[20278.056915] cdc_acm 2-2:2.1: urb 14 failed submission with -19
[20278.060418] cdc_acm 2-2:2.1: urb 15 failed submission with -19

Silence these by not logging errors when the result is -ENODEV.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Acked-by: Oliver Neukum <oneukum@suse.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-01-16 10:01:01 +01:00
Al Viro afc9a42b74 the rest of drivers/*: annotate ->poll() instances
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-11-28 11:06:58 -05:00
Linus Torvalds 894025f24b USB/PHY patches for 4.15-rc1
Here is the big set of USB and PHY driver updates for 4.15-rc1.
 
 There is the usual amount of gadget and xhci driver updates, along with
 phy and chipidea enhancements.  There's also a lot of SPDX tags and
 license boilerplate cleanups as well, which provide some churn in the
 diffstat.
 
 Other major thing is the typec code that moved out of staging and into
 the "real" part of the drivers/usb/ tree, which was nice to see happen.
 
 All of these have been in linux-next with no reported issues for a
 while.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'usb-4.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb

Pull USB/PHY updates from Greg KH:
 "Here is the big set of USB and PHY driver updates for 4.15-rc1.

  There is the usual amount of gadget and xhci driver updates, along
  with phy and chipidea enhancements. There's also a lot of SPDX tags
  and license boilerplate cleanups as well, which provide some churn in
  the diffstat.

  Other major thing is the typec code that moved out of staging and into
  the "real" part of the drivers/usb/ tree, which was nice to see
  happen.

  All of these have been in linux-next with no reported issues for a
  while"

* tag 'usb-4.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (263 commits)
  usb: gadget: f_fs: Fix use-after-free in ffs_free_inst
  USB: usbfs: compute urb->actual_length for isochronous
  usb: core: message: remember to reset 'ret' to 0 when necessary
  USB: typec: Remove remaining redundant license text
  USB: typec: add SPDX identifiers to some files
  USB: renesas_usbhs: rcar?.h: add SPDX tags
  USB: chipidea: ci_hdrc_tegra.c: add SPDX line
  USB: host: xhci-debugfs: add SPDX lines
  USB: add SPDX identifiers to all remaining Makefiles
  usb: host: isp1362-hcd: remove a couple of redundant assignments
  USB: adutux: remove redundant variable minor
  usb: core: add a new usb_get_ptm_status() helper
  usb: core: add a 'type' parameter to usb_get_status()
  usb: core: introduce a new usb_get_std_status() helper
  usb: core: rename usb_get_status() 'type' argument to 'recip'
  usb: core: add Status Type definitions
  USB: gadget: Remove redundant license text
  USB: gadget: function: Remove redundant license text
  USB: gadget: udc: Remove redundant license text
  USB: gadget: legacy: Remove redundant license text
  ...
2017-11-13 21:14:07 -08:00
Greg Kroah-Hartman 3efe891f61 USB: add SPDX identifiers to all remaining Makefiles
It's good to have SPDX identifiers in all files to make it easier to
audit the kernel tree for correct licenses.

This updates the remaining drivers/usb/*Makefile* that were missing SPDX
identifiers.  They all get the following identifier:
	SPDX-License-Identifier: GPL-2.0

The SPDX identifier is a legally binding shorthand, which can be used
instead of the full boiler plate text.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Kate Stewart <kstewart@linuxfoundation.org>
Cc: Philippe Ombredanne <pombredanne@nexb.com>
Cc: Peter Korsgaard <jacmet@sunsite.dk>
Cc: Thomas Winischhofer <thomas@winischhofer.net>
Cc: Johan Hovold <johan@kernel.org>
Acked-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-07 15:53:48 +01:00
Ingo Molnar 8c5db92a70 Merge branch 'linus' into locking/core, to resolve conflicts
Conflicts:
	include/linux/compiler-clang.h
	include/linux/compiler-gcc.h
	include/linux/compiler-intel.h
	include/uapi/linux/stddef.h

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-11-07 10:32:44 +01:00
Greg Kroah-Hartman adb393dc55 USB: class: Remove redundant license text
Now that the SPDX tag is in all USB files, that identifies the license
in a specific and legally-defined manner.  So the extra GPL text wording
can be removed as it is no longer needed at all.

This is done on a quest to remove the 700+ different ways that files in
the kernel describe the GPL license text.  And there's unneeded stuff
like the address (sometimes incorrect) for the FSF which is never
needed.

No copyright headers or other non-license-description text was removed.

Cc: Oliver Neukum <oneukum@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-04 11:55:38 +01:00
Greg Kroah-Hartman 5fd54ace47 USB: add SPDX identifiers to all remaining files in drivers/usb/
It's good to have SPDX identifiers in all files to make it easier to
audit the kernel tree for correct licenses.

Update the drivers/usb/ and include/linux/usb* files with the correct
SPDX license identifier based on the license text in the file itself.
The SPDX identifier is a legally binding shorthand, which can be used
instead of the full boiler plate text.

This work is based on a script and data from Thomas Gleixner, Philippe
Ombredanne, and Kate Stewart.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Kate Stewart <kstewart@linuxfoundation.org>
Cc: Philippe Ombredanne <pombredanne@nexb.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Acked-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-04 11:48:02 +01:00
Greg Kroah-Hartman b24413180f License cleanup: add SPDX GPL-2.0 license identifier to files with no license
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.

By default all files without license information are under the default
license of the kernel, which is GPL version 2.

Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier.  The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.

How this work was done:

Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
 - file had no licensing information it it.
 - file was a */uapi/* one with no licensing information in it,
 - file was a */uapi/* one with existing licensing information,

Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.

The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne.  Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.

The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed.  Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.

Criteria used to select files for SPDX license identifier tagging was:
 - Files considered eligible had to be source code files.
 - Make and config files were included as candidates if they contained >5
   lines of source
 - File already had some variant of a license header in it (even if <5
   lines).

All documentation files were explicitly excluded.

The following heuristics were used to determine which SPDX license
identifiers to apply.

 - when both scanners couldn't find any license traces, file was
   considered to have no license information in it, and the top level
   COPYING file license applied.

   For non */uapi/* files that summary was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0                                              11139

   and resulted in the first patch in this series.

   If that file was a */uapi/* path one, it was "GPL-2.0 WITH
   Linux-syscall-note" otherwise it was "GPL-2.0".  Results of that was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0 WITH Linux-syscall-note                        930

   and resulted in the second patch in this series.

 - if a file had some form of licensing information in it, and was one
   of the */uapi/* ones, it was denoted with the Linux-syscall-note if
   any GPL family license was found in the file or had no licensing in
   it (per prior point).  Results summary:

   SPDX license identifier                            # files
   ---------------------------------------------------|------
   GPL-2.0 WITH Linux-syscall-note                       270
   GPL-2.0+ WITH Linux-syscall-note                      169
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause)    21
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause)    17
   LGPL-2.1+ WITH Linux-syscall-note                      15
   GPL-1.0+ WITH Linux-syscall-note                       14
   ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause)    5
   LGPL-2.0+ WITH Linux-syscall-note                       4
   LGPL-2.1 WITH Linux-syscall-note                        3
   ((GPL-2.0 WITH Linux-syscall-note) OR MIT)              3
   ((GPL-2.0 WITH Linux-syscall-note) AND MIT)             1

   and that resulted in the third patch in this series.

 - when the two scanners agreed on the detected license(s), that became
   the concluded license(s).

 - when there was disagreement between the two scanners (one detected a
   license but the other didn't, or they both detected different
   licenses) a manual inspection of the file occurred.

 - In most cases a manual inspection of the information in the file
   resulted in a clear resolution of the license that should apply (and
   which scanner probably needed to revisit its heuristics).

 - When it was not immediately clear, the license identifier was
   confirmed with lawyers working with the Linux Foundation.

 - If there was any question as to the appropriate license identifier,
   the file was flagged for further research and to be revisited later
   in time.

In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.

Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights.  The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.

Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.

In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.

Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
 - a full scancode scan run, collecting the matched texts, detected
   license ids and scores
 - reviewing anything where there was a license detected (about 500+
   files) to ensure that the applied SPDX license was correct
 - reviewing anything where there was no detection but the patch license
   was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
   SPDX license was correct

This produced a worksheet with 20 files needing minor correction.  This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.

These .csv files were then reviewed by Greg.  Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected.  This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.)  Finally Greg ran the script using the .csv files to
generate the patches.

Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-02 11:10:55 +01:00
Gustavo A. R. Silva e4c6594dab usb: class: usbtmc: mark expected switch fall-through
In preparation to enabling -Wimplicit-fallthrough, mark switch cases
where we are expecting to fall through.

Signed-off-by: Gustavo A. R. Silva <garsilva@embeddedor.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-10-27 12:40:15 +02:00
Mark Rutland 6aa7de0591 locking/atomics: COCCINELLE/treewide: Convert trivial ACCESS_ONCE() patterns to READ_ONCE()/WRITE_ONCE()
Please do not apply this to mainline directly, instead please re-run the
coccinelle script shown below and apply its output.

For several reasons, it is desirable to use {READ,WRITE}_ONCE() in
preference to ACCESS_ONCE(), and new code is expected to use one of the
former. So far, there's been no reason to change most existing uses of
ACCESS_ONCE(), as these aren't harmful, and changing them results in
churn.

However, for some features, the read/write distinction is critical to
correct operation. To distinguish these cases, separate read/write
accessors must be used. This patch migrates (most) remaining
ACCESS_ONCE() instances to {READ,WRITE}_ONCE(), using the following
coccinelle script:

----
// Convert trivial ACCESS_ONCE() uses to equivalent READ_ONCE() and
// WRITE_ONCE()

// $ make coccicheck COCCI=/home/mark/once.cocci SPFLAGS="--include-headers" MODE=patch

virtual patch

@ depends on patch @
expression E1, E2;
@@

- ACCESS_ONCE(E1) = E2
+ WRITE_ONCE(E1, E2)

@ depends on patch @
expression E;
@@

- ACCESS_ONCE(E)
+ READ_ONCE(E)
----

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: davem@davemloft.net
Cc: linux-arch@vger.kernel.org
Cc: mpe@ellerman.id.au
Cc: shuah@kernel.org
Cc: snitzer@redhat.com
Cc: thor.thayer@linux.intel.com
Cc: tj@kernel.org
Cc: viro@zeniv.linux.org.uk
Cc: will.deacon@arm.com
Link: http://lkml.kernel.org/r/1508792849-3115-19-git-send-email-paulmck@linux.vnet.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-10-25 11:01:08 +02:00
Maksim Salau 765fb2f181 usb: cdc_acm: Add quirk for Elatec TWN3
Elatec TWN3 has the union descriptor on data interface. This results in
failure to bind the device to the driver with the following log:
  usb 1-1.2: new full speed USB device using streamplug-ehci and address 4
  usb 1-1.2: New USB device found, idVendor=09d8, idProduct=0320
  usb 1-1.2: New USB device strings: Mfr=1, Product=2, SerialNumber=0
  usb 1-1.2: Product: RFID Device (COM)
  usb 1-1.2: Manufacturer: OEM
  cdc_acm 1-1.2:1.0: Zero length descriptor references
  cdc_acm: probe of 1-1.2:1.0 failed with error -22

Adding the NO_UNION_NORMAL quirk for the device fixes the issue.

`lsusb -v` of the device:

Bus 001 Device 003: ID 09d8:0320
Device Descriptor:
  bLength                18
  bDescriptorType         1
  bcdUSB               2.00
  bDeviceClass            2 Communications
  bDeviceSubClass         0
  bDeviceProtocol         0
  bMaxPacketSize0        32
  idVendor           0x09d8
  idProduct          0x0320
  bcdDevice            3.00
  iManufacturer           1 OEM
  iProduct                2 RFID Device (COM)
  iSerial                 0
  bNumConfigurations      1
  Configuration Descriptor:
    bLength                 9
    bDescriptorType         2
    wTotalLength           67
    bNumInterfaces          2
    bConfigurationValue     1
    iConfiguration          0
    bmAttributes         0x80
      (Bus Powered)
    MaxPower              250mA
    Interface Descriptor:
      bLength                 9
      bDescriptorType         4
      bInterfaceNumber        0
      bAlternateSetting       0
      bNumEndpoints           1
      bInterfaceClass         2 Communications
      bInterfaceSubClass      2 Abstract (modem)
      bInterfaceProtocol      1 AT-commands (v.25ter)
      iInterface              0
      Endpoint Descriptor:
        bLength                 7
        bDescriptorType         5
        bEndpointAddress     0x83  EP 3 IN
        bmAttributes            3
          Transfer Type            Interrupt
          Synch Type               None
          Usage Type               Data
        wMaxPacketSize     0x0020  1x 32 bytes
        bInterval               2
    Interface Descriptor:
      bLength                 9
      bDescriptorType         4
      bInterfaceNumber        1
      bAlternateSetting       0
      bNumEndpoints           2
      bInterfaceClass        10 CDC Data
      bInterfaceSubClass      0 Unused
      bInterfaceProtocol      0
      iInterface              0
      Endpoint Descriptor:
        bLength                 7
        bDescriptorType         5
        bEndpointAddress     0x02  EP 2 OUT
        bmAttributes            2
          Transfer Type            Bulk
          Synch Type               None
          Usage Type               Data
        wMaxPacketSize     0x0020  1x 32 bytes
        bInterval               0
      Endpoint Descriptor:
        bLength                 7
        bDescriptorType         5
        bEndpointAddress     0x81  EP 1 IN
        bmAttributes            2
          Transfer Type            Bulk
          Synch Type               None
          Usage Type               Data
        wMaxPacketSize     0x0020  1x 32 bytes
        bInterval               0
      CDC Header:
        bcdCDC               1.10
      CDC Call Management:
        bmCapabilities       0x03
          call management
          use DataInterface
        bDataInterface          1
      CDC ACM:
        bmCapabilities       0x06
          sends break
          line coding and serial state
      CDC Union:
        bMasterInterface        0
        bSlaveInterface         1
Device Status:     0x0000
  (Bus Powered)

Signed-off-by: Maksim Salau <msalau@iotecha.com>
Acked-by: Oliver Neukum <oneukum@suse.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-10-17 11:04:32 +02:00
Bjørn Mork 8fec9355a9 USB: cdc-wdm: ignore -EPIPE from GetEncapsulatedResponse
The driver will forward errors to userspace after turning most of them
into -EIO. But all status codes are not equal. The -EPIPE (stall) in
particular can be seen more as a result of normal USB signaling than
an actual error. The state is automatically cleared by the USB core
without intervention from either driver or userspace.

And most devices and firmwares will never trigger a stall as a result
of GetEncapsulatedResponse. This is in fact a requirement for CDC WDM
devices. Quoting from section 7.1 of the CDC WMC spec revision 1.1:

  The function shall not return STALL in response to
  GetEncapsulatedResponse.

But this driver is also handling GetEncapsulatedResponse on behalf of
the qmi_wwan and cdc_mbim drivers. Unfortunately the relevant specs
are not as clear wrt stall. So some QMI and MBIM devices *will*
occasionally stall, causing the GetEncapsulatedResponse to return an
-EPIPE status. Translating this into -EIO for userspace has proven to
be harmful. Treating it as an empty read is safer, making the driver
behave as if the device was conforming to the CDC WDM spec.

There have been numerous reports of issues related to -EPIPE errors
from some newer CDC MBIM devices in particular, like for example the
Fibocom L831-EAU.  Testing on this device has shown that the issues
go away if we simply ignore the -EPIPE status.  Similar handling of
-EPIPE is already known from e.g. usb_get_string()

The -EPIPE log message is still kept to let us track devices with this
unexpected behaviour, hoping that it attracts attention from firmware
developers.

Cc: <stable@vger.kernel.org>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=100938
Reported-and-tested-by: Christian Ehrig <christian.ehrig@mediamarktsaturn-bt.com>
Reported-and-tested-by: Patrick Chilton <chpatrick@gmail.com>
Reported-and-tested-by: Andreas Böhler <news@aboehler.at>
Signed-off-by: Bjørn Mork <bjorn@mork.no>
Acked-by: Oliver Neukum <oneukum@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-09-25 10:57:13 +02:00
Arvind Yadav a70df9641f usb: usbtmc: constify attribute_group structures.
attribute_group are not supposed to change at runtime. All functions
working with attribute_group provided by <linux/sysfs.h> work with
const attribute_group. So mark the non-const structs as const.

Signed-off-by: Arvind Yadav <arvind.yadav.cs@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-08-10 11:31:28 -07:00
Greg Kroah-Hartman 141769851c Merge 4.13-rc2 into usb-next
We want the USB fixes in here as well.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-23 19:55:51 -07:00
Greg Kroah-Hartman 2440bbc529 USB: cdc-wdm: remove unneeded DRIVER_VERSION define
No one uses the DRIVER_VERSION define in this driver, so just delete it.

Cc: Oliver Neukum <oneukum@suse.com>
Cc: "Bjørn Mork" <bjorn@mork.no>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-22 15:56:53 +02:00
Johan Hovold fe855789d6 USB: cdc-acm: add device-id for quirky printer
Add device-id entry for DATECS FP-2000 fiscal printer needing the
NO_UNION_NORMAL quirk.

Reported-by: Anton Avramov <lukav@lukav.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
Acked-by: Oliver Neukum <oneukum@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-17 13:11:56 +02:00
Geliang Tang 64b9533ec1 usb: cdc-wdm: use memdup_user
Use memdup_user() helper instead of open-coding to simplify the code.

Signed-off-by: Geliang Tang <geliangtang@gmail.com>
Acked-by: Oliver Neukum <oneukum@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-17 12:20:53 +02:00
Bjørn Mork 1944581699 USB: Revert "cdc-wdm: fix "out-of-sync" due to missing notifications"
This reverts commit 833415a3e7 ("cdc-wdm: fix "out-of-sync" due to
missing notifications")

There have been several reports of wdm_read returning unexpected EIO
errors with QMI devices using the qmi_wwan driver. The reporters
confirm that reverting prevents these errors. I have been unable to
reproduce the bug myself, and have no explanation to offer either. But
reverting is the safe choice here, given that the commit was an
attempt to work around a firmware problem.  Living with a firmware
problem is still better than adding driver bugs.

Reported-by: Kasper Holtze <kasper@holtze.dk>
Reported-by: Aleksander Morgado <aleksander@aleksander.es>
Reported-by: Daniele Palmas <dnlplm@gmail.com>
Cc: <stable@vger.kernel.org> # v4.9+
Fixes: 833415a3e7 ("cdc-wdm: fix "out-of-sync" due to missing notifications")
Signed-off-by: Bjørn Mork <bjorn@mork.no>
Acked-by: Oliver Neukum <oneukum@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-04-25 20:04:28 +02:00
Mauro Carvalho Chehab 21470e32ca usb: fix some references for /proc/bus/usb
Since when we got rid of usbfs, the /proc/bus/usb is now
elsewhere. Fix references for it.

Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Acked-by: Serge Hallyn <serge@hallyn.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-04-18 16:54:19 +02:00
Tobias Herzog d30eed1cd2 cdc-acm: remove unused element of struct acm
write_used was introduced with commit 884b600f63 ("[PATCH] USB: fix acm
trouble with terminals") but never used since.

Signed-off-by: Tobias Herzog <t-herzog@gmx.de>
Acked-by: Oliver Neukum <oneukum@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-04-01 11:05:03 +02:00
Tobias Herzog 2d6dfd17ae cdc-acm: log message for serial state notification
Adds a similar log message to USB_CDC_NOTIFY_SERIAL_STATE as it is
already done with USB_CDC_NOTIFY_NETWORK_CONNECTION.

Signed-off-by: Tobias Herzog <t-herzog@gmx.de>
Acked-by: Oliver Neukum <oneukum@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-04-01 11:05:03 +02:00
Tobias Herzog ea2583529c cdc-acm: reassemble fragmented notifications
USB devices may have very limited endpoint packet sizes, so that
notifications can not be transferred within one single usb packet.
Reassembling of multiple packages may be necessary.

Signed-off-by: Tobias Herzog <t-herzog@gmx.de>
Acked-by: Oliver Neukum <oneukum@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-04-01 11:05:03 +02:00
Tobias Herzog 1bb9914e17 cdc-acm: fix possible invalid access when processing notification
Notifications may only be 8 bytes long. Accessing the 9th and
10th byte of unimplemented/unknown notifications may be insecure.
Also check the length of known notifications before accessing anything
behind the 8th byte.

Signed-off-by: Tobias Herzog <t-herzog@gmx.de>
Acked-by: Oliver Neukum <oneukum@suse.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-04-01 11:05:03 +02:00
Johan Hovold 041370cce8 USB: usbtmc: refactor endpoint retrieval
Use the new endpoint helpers to lookup the required bulk-in and bulk-out
endpoints, and the optional interrupt-in endpoint.

Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-03-29 11:53:15 +02:00
Greg Kroah-Hartman e47ff590cc Merge 4.11-rc4 into usb-next
This resolves a merge issue in the gadget code, and we want the USB
fixes in here as well.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-03-27 09:19:32 +02:00
Johan Hovold 5370860a1f USB: usblp: refactor endpoint retrieval
Use the new endpoint helpers to lookup the required bulk-out endpoint
and the depending on protocol likewise required bulk-in endpoint.

Cc: Pete Zaitcev <zaitcev@redhat.com>
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-03-23 13:54:08 +01:00
Johan Hovold f8d8464bfc USB: cdc-acm: refactor endpoint retrieval
Use the new endpoint helpers to lookup the required bulk-in, bulk-out
and interrupt-in endpoints for collapsed interfaces.

Note that there is already a check verifying that there are exactly
three endpoints so we'd still be bailing out if there's an unexpected
endpoint type.

Cc: Oliver Neukum <oneukum@suse.com>
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-03-23 13:54:08 +01:00
Johan Hovold 2e47c53503 USB: usbtmc: fix probe error path
Make sure to initialise the return value to avoid having allocation
failures going unnoticed when allocating interrupt-endpoint resources.

This prevents use-after-free or worse when the device is later unbound.

Fixes: dbf3e7f654 ("Implement an ioctl to support the USMTMC-USB488 READ_STATUS_BYTE operation.")
Cc: stable <stable@vger.kernel.org>     # 4.6
Cc: Dave Penkler <dpenkler@gmail.com>
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-03-17 13:22:58 +09:00
Johan Hovold 687e0687f7 USB: usbtmc: add missing endpoint sanity check
USBTMC devices are required to have a bulk-in and a bulk-out endpoint,
but the driver failed to verify this, something which could lead to the
endpoint addresses being taken from uninitialised memory.

Make sure to zero all private data as part of allocation, and add the
missing endpoint sanity check.

Note that this also addresses a more recently introduced issue, where
the interrupt-in-presence flag would also be uninitialised whenever the
optional interrupt-in endpoint is not present. This in turn could lead
to an interrupt urb being allocated, initialised and submitted based on
uninitialised values.

Fixes: dbf3e7f654 ("Implement an ioctl to support the USMTMC-USB488 READ_STATUS_BYTE operation.")
Fixes: 5b775f672c ("USB: add USB test and measurement class driver")
Cc: stable <stable@vger.kernel.org>     # 2.6.28
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-03-17 13:22:58 +09:00
Ingo Molnar 174cd4b1e5 sched/headers: Prepare to move signal wakeup & sigpending methods from <linux/sched.h> into <linux/sched/signal.h>
Fix up affected files that include this signal functionality via sched.h.

Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-02 08:42:32 +01:00
Gustavo A. R. Silva 53b7f7b53d usb: cdc-wdm: remove logically dead code
Remove logically dead code.
'cntr' is always equal to zero when the following line of code is executed:
rv = cntr ? cntr : -EAGAIN;

Addresses-Coverity-ID: 113227
Signed-off-by: Gustavo A. R. Silva <garsilva@embeddedor.com>
Acked-by: Oliver Neukum <oneukum@suse.com>
Reviewed-by: Peter Senna Tschudin <peter.senna@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-02-15 10:35:15 -08:00
Johan Hovold 4ddecf76b5 USB: cdc-acm: fix TIOCGSERIAL flags
The driver reports that it always uses a low-latency mode by returning
the ASYNC_LOW_LATENCY flag through TIOCGSERIAL.

Even if this behaviour could not be changed, this may have made some
sense prior to 7a9a65ced1 ("cdc-acm: Fix long standing abuse of
tty->low_latency") which removed the unconditional setting of the
corresponding tty low_latency flag (something which had always been
broken in itself).

Since the driver does not have a low-latency mode, let's drop the flag.

Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-26 18:51:15 +01:00
Nathaniel Quillin 301216044e USB: cdc-acm: add device id for GW Instek AFG-125
Add device-id entry for GW Instek AFG-125, which has a byte swapped
bInterfaceSubClass (0x20).

Signed-off-by: Nathaniel Quillin <ndq@google.com>
Acked-by: Oliver Neukum <oneukum@suse.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-12-05 16:32:51 +01:00
Ladislav Michl 1aba579f3c cdc-acm: handle read pipe errors
Read urbs are submitted back only on success, causing read pipe
running out of urbs after few errors. No more characters can
be read from tty device then until it is reopened and no errors
are reported.
Fix that by always submitting urbs back and clearing stall on
-EPIPE.

Signed-off-by: Ladislav Michl <ladis@linux-mips.org>
Acked-by: Oliver Neukum <oneukum@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-11-21 11:36:16 +01:00
Ladislav Michl d305394ee8 cdc-acm: remove is_int_ep from acm structure
is_int_ep is used only in acm_probe, no need to store it in device data.

Signed-off-by: Ladislav Michl <ladis@linux-mips.org>
Acked-by: Oliver Neukum <oneukum@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-11-21 11:36:15 +01:00
Ladislav Michl 74bccc9b71 cdc-acm: store in and out pipes in acm structure
Clearing stall needs pipe descriptor, store it in acm structure.

Signed-off-by: Ladislav Michl <ladis@linux-mips.org>
Acked-by: Oliver Neukum <oneukum@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-11-21 11:36:15 +01:00
Ladislav Michl ba8c931ded cdc-acm: refactor killing urbs
Move urb killing code into separate function and use it
instead of copying that code pattern over.

Signed-off-by: Ladislav Michl <ladis@linux-mips.org>
Acked-by: Oliver Neukum <oneukum@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-11-21 11:36:15 +01:00
Ladislav Michl e46146069b cdc-acm: avoid interface_to_usbdev call
Pointer to usb_device is already stored in acm structure.

Signed-off-by: Ladislav Michl <ladis@linux-mips.org>
Acked-by: Oliver Neukum <oneukum@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-11-21 11:36:15 +01:00
Ladislav Michl 90744af8b0 cdc-acm: reindent log messages
Use only one tab to indent dev_{(v)dbg,err} parameters.

Signed-off-by: Ladislav Michl <ladis@linux-mips.org>
Acked-by: Oliver Neukum <oneukum@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-11-21 11:36:15 +01:00
Greg Kroah-Hartman 8a0a8e1c42 Merge 4.9-rc5 into usb-next
We want/need the USB fixes in here as well, for testing and merge
issues.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-11-14 08:11:29 +01:00
Johan Hovold bb2d387c4d USB: cdc-acm: use get_icount tty operation
Use the tty get_icount operation instead of implementing TIOCGICOUNT
directly.

Signed-off-by: Johan Hovold <johan@kernel.org>
Acked-by: Oliver Neukum <oneukum@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-11-10 13:16:57 +01:00
Johan Hovold 04cbf3832b USB: cdc-acm: fix invalid user-pointer check
Drop invalid user-pointer check from TIOCGSERIAL handler.

A NULL-pointer can be valid in user space and copy_to_user() takes care
of sanity checking.

Signed-off-by: Johan Hovold <johan@kernel.org>
Acked-by: Oliver Neukum <oneukum@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-11-10 13:16:57 +01:00
Johan Hovold 18266403f3 USB: cdc-acm: fix TIOCMIWAIT
The TIOCMIWAIT implementation would return -EINVAL if any of the three
supported signals were included in the mask.

Instead of returning an error in case TIOCM_CTS is included, simply
drop the mask check completely, which is in accordance with how other
drivers implement this ioctl.

Fixes: 5a6a62bdb9 ("cdc-acm: add TIOCMIWAIT")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
Acked-by: Oliver Neukum <oneukum@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-11-10 13:12:59 +01:00
Oliver Neukum 7309aa847e cdc-acm: fix uninitialized variable
variable struct usb_cdc_parsed_header h may be used
uninitialized in acm_probe.

In kernel 4.8.

    /* handle quirks deadly to normal probing*/
    if (quirks == NO_UNION_NORMAL)

        ...

        goto skip_normal_probe;
    }

we bypass call to

    cdc_parse_cdc_header(&h, intf, buffer, buflen);

but later use h in

    if (h.usb_cdc_country_functional_desc) { /* export the country data */

Signed-off-by: Oliver Neukum <oneukum@suse.com>
CC: stable@vger.kernel.org
Reported-by: Victor Sologoubov <victor0@rambler.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-11-07 10:15:22 +01:00
Dave Penkler 88aecde40b usbtmc: Add, clarify and fix comments
Add information regarding lifespan of kref protection:
   Clarify comment on kref_get for interrupt in urb in usbtmc_probe()
   Add comment on kref_get in usbtmc_open()

Fix endpoint reference in documentation for send_request_dev_dep_msg_in()

Signed-off-by: Dave Penkler <dpenkler@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-10-24 14:36:25 +02:00